What is the primary function of a laminar-flow hood in a laboratory?

• A. It humidifies the air
• B. It projects clean filtered air onto the work surface
• C. It generates ultraviolet sterilization
• D. It stores specimens

Answer: (B)

Laminar-flow hoods project a steady, filtered air stream across the work surface in one direction. This unidirectional flow sweeps away dust and particulates, helping keep the samples uncontaminated during handling. The air is filtered (usually by a HEPA filter) before it reaches the work area, so the environment around the sample stays clean. It doesn’t humidify the air, it isn’t used for UV sterilization during operation, and it isn’t meant to store specimens.